Lamotrigine is known as 6-(2,3-Dichlorophenyl)-1,2,4-triazine-3,5-diamine or 3,5-diamine-6-(2,3-dichlorophenyl)-1,2,4-triazine and has the following chemical formula (I).

Lamotrigine is an anti-epileptic drug of the phenyltriazine class and is chemically unrelated to other existing anti-epileptic drugs. This drug is produced by GlaxoWellcome and is sold under the trademark LAMICTAL®. LAMICTAL® is produced in the form of chewable dispersible tablets and is available in different strengths (from 2 mg to 200 mg).
The crystallographic structure of lamotrigine methanolate is known (Acta Cryst., (1989, C45, 129-132)).
No indication was found in the literature concerning the existence of other types of crystal forms of lamotrigine. There is a need to develop various crystal forms of lamotrigine for better formulation.